On a shelf, there were 70 hoodies and sweaters. Bobby spilt tea on the shelf and stained 50% of the sweaters and 20% of the hoodies. If 53 hoodies and sweaters were still clean, how many clean sweaters were there?
|
Hoodies |
Sweaters |
Total |
Stained |
1 u |
1 p |
17 |
Clean |
4 u |
1 p |
53 |
Total |
5 u |
2 p |
70 |
50% =
50100 =
12 20% =
20100 =
15 Number of stained clothes
= 70 - 53
= 17
4 u + 1 p = 53
1 p = 53 - 4 u --- (1)
1 u + 1 p = 17
1 p = 17 - 1 u --- (2)
(2) - (1)
17 - 1 u = 53 - 4 u
4 u - 1 u = 53 - 17
3 u = 36
1 u = 36 ÷ 3 = 12
Number of clean sweaters is the same as the number of stained sweaters.
Number of clean sweaters
= 17 - 1 u
= 17 - 12
= 5
Answer(s): 5